Downloaded and installed mod packs via the guide. There's only one problem I've run into: the description messages (question marks) don't seem to be appearing where they should be. In the vanilla version, the text would show up where I clicked, but with the mod pack, they seem to show up in the middle of the screen instead.

I noticed that too. Doesn't bother me much though.

...Maybe it's a feature of the mod? Perhaps fiddling through an .ini file or something might help?